T-Mobile has revamped its data plans to include a cap system, thus leaving Sprint as the only major U.S. wireless carrier to offer uncapped 4G mobile data plans.

T-Mobile's caps are significantly different from AT&T's and Verizon's, however, in that they don't charge overage fees to users who exceed their monthly caps. Instead, T-Mobile will knock down users who go over the cap to its 2G EDGE network, thus effectively limiting the amount of data they can consume on their HSPA+ network and slowing down their connection speed.

The T-Mobile caps also offer more bang for the buck than the plans offered by Verizon and AT&T. The carrier is offering four different monthly data plans: a 200MB plan for $10 a month; a 2GB plan for $20 a month; a 5GB plan for $30 a month; and a 10GB plan for $60 per month. AT&T, by contrast, charges iPad users $15 a month for 250MB of data and $25 a month for 2GB of data. Verizon, meanwhile, offers a 1GB plan for $20, a 3GB plan for $35, a 5GB plan for $50 and a 10GB plan for $80.

But while T-Mobile's data plans are cheaper and don't impose monetary penalties for overages, its decision to implement data caps means that Sprint is now the only carrier that isn't placing any limits on use of its 4G network, based on the WiMAX mobile broadband standard. Sprint CEO Dan Hesse has consistently said that Sprint and its partners at Clearwire have a strong enough combined spectrum portfolio to offer users unlimited mobile data without capping what they use. He has also said that the company could keep its plans unlimited by charging more if it eventually found that customers were consuming more data than the carrier could handle. Sprint still maintains a 5GB data cap for data consumed on its 3G EV-DO Rev. A network, however.

The wireless industry has been moving away from all-you-can-eat data plans and toward tiered service plans for the past couple of years. AT&T got the ball rolling on wireless data caps last year when it announced it was dropping unlimited data plans for the iPhone in favor of plans that offered between 200MB and 2GB of data consumption per month. Verizon shortly followed suit by saying it would implement a similar pricing scheme for its 4G LTE services that launched commercially in December.

AT&T has also said that it will start imposing data caps on its wireline services by slapping its DSL customers with a 150GB cap and its U-Verse customers with a 250GB cap. AT&T says that it will only charge for overages if wireline users exceed their monthly caps three times or more, however.